Use of A1C for Screening and Diagnosis of Type 2 Diabetes in Three Rural Health Care Systems

T he prevalence of type 2 diabetes continues to escalate in the United States. An estimated 26 million people have been diagnosed with type 2 diabetes; an additional 79 million have prediabetes and are at risk for developing the disease.1 Lifestyle interventions to reduce the risk of type 2 diabetes in at-risk individuals may be beneficial.2–5 Effective screening for type 2 diabetes in the primary care population may improve outcomes.5,6 Traditionally, fasting plasma glucose (FPG) measurement, casual (random) plasma glucose testing, and oral glucose tolerance tests (OGTTs) have been the standard of care for screening and diagnosis of diabetes.7 A1C has not been recommended as a diabetes screening or diagnostic test. Rather, this measure, which reflects average blood glucose during an approximately 3-month time span, has been used to monitor diabetes treatment and as a predictor of potential diabetes complications.7 Following the recommendation of an international expert committee and based on data from the National Health and Nutrition Examination Survey and other sources,8 the American Diabetes Association (ADA) added A1C to its criteria for screening for and diagnosing diabetes in January 2010.7 This study evaluated trends in A1C testing used to screen for and diagnose type 2 diabetes in three rural health care systems in the upper Midwest after the 2010 change in ADA guidelines. Additionally, it surveyed health care providers to assess their knowledge and attitudes pertaining to screening for and diagnosing type 2 diabetes. A1C test results used for analysis in this retrospective review of electronic medical record (EMR) charts were obtained from individuals receiving an A1C test in 2009 and 2010 (before and after, respectively, the 2010 change in the ADA recommendations) in three health care systems in the Red River Valley of North Dakota and …